Synthesis of Mealy machines using derivatives

In Rutten [16] the theoretical basis was given for the synthesis of binary Mealy machines from specifications in 2-adic arithmetic. This construction is based on the symbolic computation of the coalgebraic notion of stream function derivative, a generalisation of the Brzozowski derivative of regular expressions. In this paper we complete the construction of Mealy machines from specifications in both 2-adic and modulo-2 arithmetic by describing how we decide equivalence of expressions via reduction to normal forms; we present a Haskell implementation of this Mealy synthesis algorithm; and a theoretical result which characterises the (number of) states in Mealy machines constructed from rational 2-adic specifications

Automated verification of executable UML models

We present a fully automated approach to verifying safety properties of Executable UML models (xUML). Our tool chain consists of a model transformation program which translates xUML models to the process algebra mCRL2, followed by symbolic model checking using LTSmin. If a safety violation is found, an error trace is visualised as a UML sequence diagram. As a novel feature, our approach allows safety properties to be specified as UML state machines